The satisfactory removal of soils/stains from soiled/stained substrates is a particular challenge to the formulator of a detergent composition for use in a washing method such as a laundry or machine dishwashing method.
Traditionally, the removal of such soils/stains has been enabled by the use of bleach components such as oxygen bleaches, including hydrogen peroxide and organic peroxyacids. The organic peroxyacids are often obtained by the in situ perhydrolysis reaction between hydrogen peroxide and an organic peroxyacid bleach precursor, so called "bleach precursor".
A problem encountered with the use of bleach precursors is that upon cold temperature washing solutions (5.degree. C. to 30.degree. C.) or under high water hardness conditions, the solubilisation rate of the precursors is decreased. As the perhydrolysis rate is reduced, so does the cleaning performance. Such a problem of low solubilisation or dissolution is further exarcerbated where the precursor exhibits surfactancy properties. Typical examples of such precursors are the amide substituted bleach precursor compounds such as (6-octanamido-caproyl) oxy benzene sulfonate, (6-nonanamidocaproyl) oxy benzene sulfonate and (6-decanamido-caproyl) oxy benzene sulfonate as described in EP-A-0170386. Accordingly, the formulator of a bleach precursor composition is faced with the challenge of formulating a bleach precursor composition which provides effective solubilisation or dissolution of the precursor.
To solve this problem of low dissolution, the coating and/or agglomeration of the bleach precursor with a water-soluble material has been proposed as described in co-pending application PCT/US95/15494.
However, notwithstanding the advances in the art, there is still a need for an alternative composition which provides effective dissolution of the bleach precursor.
The Applicant has now found that this problem can be overcome by the provision of a peroxyacid bleach precursor in combination with a surfactant system comprising a non-ethoxylated anionic surfactant and a nonionic surfactant.